Gonado-hepatosomatic Indexes of Clarias gariepinus Sub-adult Exposed to Artrazine, Cocos nucifera Water and Phyllanthus muelarianus Extract

Food provision the world over has always been lower than demand. Man from antiquity keeps making effort to bridge the gap between food provision and need. However, some foods could be provided in excess. Some vital foods like animal protein are poorly consumed in tropical Africa due to their inadequacy. Being aware of the dwindling natural resources, man continues to shift his emphasis from food capture to culture in order to be able to use a small area to produce high quantity of the food. Culturing aims at manipulating food chains to favour the desired species. The quality of feeds for a proper culture medium should contain the varying nutrients in the proper proportion. Environment (internal or external) of the fish is very important in its health and growth. External environment include the quality and quantity of food available, the presence or absence of xenobiotics and pollutants. Clarias are important food fishes because of their large size, good flavour and rapid growth [1]. They are cosmopolitan and are widely cultured fish in the tropics and subtropics, and the third only to carp and tilapia, widely farmed fresh water fish in the world [2]. Presently, weed management has become a more serious problem because land fallowing, which was a method for controlling weeds in the tropics is no more tenable. It is observed that weed infestation is a limiting factor in farm size expansion in sub-Saharan Africa). Having realized that chemical method is cheaper than hand weeding, this method has gained ground in recent times and thus results in the introduction of more of these herbicides into the natural aquatic system now and in feature (U. S. EPA, 1993).


Introduction
Food provision the world over has always been lower than demand. Man from antiquity keeps making effort to bridge the gap between food provision and need. However, some foods could be provided in excess. Some vital foods like animal protein are poorly consumed in tropical Africa due to their inadequacy. Being aware of the dwindling natural resources, man continues to shift his emphasis from food capture to culture in order to be able to use a small area to produce high quantity of the food. Culturing aims at manipulating food chains to favour the desired species. The quality of feeds for a proper culture medium should contain the varying nutrients in the proper proportion. Environment (internal or external) of the fish is very important in its health and growth. External environment include the quality and quantity of food available, the presence or absence of xenobiotics and pollutants. Clarias are important food fishes because of their large size, good flavour and rapid growth [1]. They are cosmopolitan and are widely cultured fish in the tropics and subtropics, and the third only to carp and tilapia, widely farmed fresh water fish in the world [2]. Presently, weed management has become a more serious problem because land fallowing, which was a method for controlling weeds in the tropics is no more tenable. It is observed that weed infestation is a limiting factor in farm size expansion in sub-Saharan Africa). Having realized that chemical method is cheaper than hand weeding, this method has gained ground in recent times and thus results in the introduction of more of these herbicides into the natural aquatic system now and in feature (U. S. EPA, 1993).
The indiscriminate use of pesticides, careless handling, accidental spillage and discharge of untreated effluents into natural water bodies have harmful effects on fish population and other forms of aquatic life and may also have long-term adverse effects on the environment. Apart from finding the hindrances of fish health, other substances, which man uses as food or medicines, are incorporatable in the fish culture environment to enhance their growth or investigate their influences.
In the natural environment, abnormalities in gonads were investigated in natural habitat of whitefish by Bernet et al. [3] in Lake Thun. Some abnormalities recorded include adhesions/fusions to the peritoneal wall and the lateral trunk musculature, asymmetry, atrophy, compartmentations, constrictions and hermaphroditism. Stentiford et al. [4] investigated the histopathological alterations in selected organs and tissues of three species of estuarine fish (Platichthys flesus, Pomatoschistus minutus and Zoarces viviparus), captured from four British estuaries (the Tyne, Tees, Mersey and Alde) differently impacted by contaminants. Sampson et al. opined that flatfish (Pleuronectes platessa) are in close contact with sediments and are thus exposed to xenobiotics stored in the sediments and were observed to alter the histology of their liver, kidney and gonads in Mersey Estuary. Other studies carried out on the effects of agrotoxicants on fish are those of Oloruntuyi et al. [5] who worked on the toxicity of Glyphosate and Gramoxone to Clarias giriepinus; Agbon et al. [6] carried out a renewable static experiment on the toxicity of Diaxonon on rotifers, Cyclops, mosquito larvae and fish; Kori-Siakpere et al. [7] investigated the effects of sublethal Paraquat on blood plasma and organic constituents of African catfish. Also, Ayotunde [8] determined the toxicity of Moringa oleifera seeds on the juvenile and adults of Nile tilapia and African catfish and Ayotunde et al. [9] exposed adult Clarias gariepinus to pawpaw seed extracts to observe their Atrazine and coco nut water killed fish at various concentrations as expressed in Table 1 and Figures 1-12. It also did not change dissolved oxygen concentration and pH outside the normal range for fish survival in Figures 11 and 12.

Discussion
Death of organisms in any environment could result from several factors. Toxins introduced into the tanks could attack the organisms in haematological changes. Ada et al. [10,11] investigated the influence of several herbicides (Glyphosate, Paraquat, Artrazine and Butachlor) on the hapatosomatic index of Nile Tilapia (Oreochromis niloticus) and the influence of Aloe barbadensis on white blood cell counts of adult Heterobranchus bidorsalis.
Atrazine is one of the two most widely used herbicides, and Atrazine has been suspected to be associated with hormonal system disruption in vertebrates (U. S. EPA, 2000) [12]. Some herbicides can be transferred from one location to the other through water flow or by bioaccumulation along food chains.
The genus Phyllanthus is said to be the largest of the Angiosperms and has a large number of medically important species for man. Some species are said to have potential effects against hepatitis B and antiviral activity against human immunodeficiency virus [13]. Phyllanthus muellerianus extracts are antimicrobial [14,15]. It is used in the treatment of various liver disorders in India. In Thailand, Phyllanthus amarus (Schum. & Thonn) has also been widely used as an antipyretic, a diuretic, to treat liver diseases and viral infections [16].
Its medicinal importance is due to the presence of the phytochemical compositions. Members of the Genus Phyllanthus have been observed to contain the following active ingredients: alkaloids, coumarins, flavoids, phenols, steroids, saponins, tritaponoids, glucosides and dihydrochalcones [17].
It is the desire of the researcher to investigate into the influence of Phyllanthus muelarianus extract, Cocos nucifera water and the herbicide Artrazine on the gonado-hapatosomatic indexes of Clarias gariepinus, as important organs of this fish, and to determine the effects of different concentrations of substances on the biological behaviours such as air gulping, erratic swimming, operculation, discolouration, haemorhage, loss of reflex on the African catfish (Clarias gariepinus).

Methods
The fish were weighed using a digital balance Model EK-5350 to the nearest mg, while length was measured using a measuring board to the nearest mm. The liver was removed and weighed using a digital balance (Scout-pro SPU402). The hepatosomatic index was obtained by dividing the weight of the liver by the total weight of the fish [18] expressed as a percentage. The gonadosomatic index was estimated in the same way [11,19]. After exposure, five fish were measured in each tank and their averages taken. Temperature, conductivity and pH were measured using digital meter mettle Toledo 320.
To each 40 L of stream water drawn from Department of Fisheries and Aquatic Science, CRUTECH, fish farm, ten fish selected randomly from a parent population were cultured. The concentration of Atrazine in the definitive experiment were 0.0 mg/L, 3.0 mg/L, 6.0 mg/L, 9. Acute toxicity experiments were conducted for four days in tests involving Atrazine and coconut water. In the test involving Phyllanthus muellarianus, the experiment lasted for 15 days to provide enough time for any observable physiological change. Fish were fed 6 % using industrially made pelleted feed (COUPENS), unlike in experiment involving coconut water and Atrazine.

Results
Phyllanthus muelarianus did not kill any of the exposed fish.   their physiological systems. For instance, it was observed that coconut water did not change the temperature in the cultured tanks irrespective of the concentration. But it influenced the pH of the water in the tanks. Coconut water reduced dissolved oxygen concentration. Insufficient dissolved oxygen in water is capable of causing malfunction in many metabolic processes. Coconut water also raised the pH of the water above the optimum range of 6.5 to 8.5 [20][21][22]. WHO'S classification of Atrazine is in class II. Coconut water has thus far not been classified. It killed the organisms at very high concentrations unlike Atrazine. Phyllanthus did not cause any mortality. It is rather a health booster. It Concentration of Cocos nucifera water (mg/L) Figure 3: Temperature variation in water exposed in different aquaria exposed to different concentrations of coconut water. The temperature did not differ significantly among the aquaria.      Figure 12: Gonado-hepatosomatic indexes of sub adult Clariasgariepinus exposed to Phyllanthus muellarianus extract. Statistical analysis showed no significant difference among treatments (ɑ = 0.05) [23] pointed that apart from the mortality of adult fish, xenobiotics affect egg hatchability and fingerling survival and growth. According to APHA [24] 'the 48-96 hour LC 50 values are useful values of relative acute lethal toxicity to organisms under specific conditions. These values do not represent the safe concentration in the natural habitats', because long term contact with much lower concentrations may be lethal to fish and may cause a lethal impairment of their functions. Langiano and Martinez [25] observed increase in plasma glucose in fish  was not seen to change neither the pH nor the dissolved oxygen outside the normal range for fish optimal survival.

Conclusion
Both liver and gonads were observed not to be affected by both factors (test substances) described as life enhancing and threatening respectively. This lack of observation was not enough to conclude that these substances did not cause harm to the organisms. Jauncey and Ross exposed to 10 mg/L of Glyphosate, indicating a typical stress response. There was also increase in catalase liver activity in fish exposed to 10 mg/L of the herbicide, suggesting the activation of antioxidant defenses after Roundup exposure. The herbicide also induced several liver histological alterations that might impair normal organ functioning. Similar results were noticed by Ada et al., [26].
Biological and behavioural changes as reported in Tables 1-3 are immediate. Gross morphological changes has to be cumulative and do take a longer time to manifest. Longer term effect of herbicide is that of the endocrine or hormonal system disruption. By disrupting the hormonal system, a wide range of biological processes such as control of blood sugar, growth and function of reproductive system, regulation of metabolism, brain and nervous system development and development of an organism from conception to adulthood may become impossible [12]. The possibility of synergism or antagonism and other multiple effects or multiple toxicants must be considered. Jones [27] and Brown and Sadler [28] as well as other workers cited in Kori -Siakpere and Ubogu [29] reported association of heavy metal toxicity.
These substances may cause changes in the liver which is a detoxification centre [30]. The liver has to carry out defensive mechanism to be able to detoxify poisons and since these substances are highly attracted to the organ, the liver. It is therefore an organ that has to be highly protected.  Table 3: Behavioural and biological observations that occurred in sub-adult Clarias gariepinus exposed to Cocos nucifera water. N = no response of fish at that particular concentration while Y = yes there was response.